Friday, 14 December 2018

Feldman & Conee Evidentialism and Incomplete Evidence

In a recent essay, “Between Belief and
Disbelief”, R. Feldman and E. Conee (F&C) defend the following
evidentialist thesis:

(EC)Believing is the justified attitude when the
person’s evidence on balance supports a proposition, disbelieving the justified
attitude when the person’s evidence on balance supports the negation of a
proposition, and suspension of judgement is the justified attitude when the
person’s evidence on balance supports neither a proposition nor its negation.

F&C observe that (EC) “implies that
even slight support is sufficient to make belief justified”(p. 76). In this
respect, (EC) stands in contrast to views according to which an agent may be
justified in suspending judgement about P
even if their evidence slightly supports P
over ¬P. F&C motivate (EC) with the following
claim:

“Barely indicating truth is still
indicating truth. Believing fits with this indication; withholding judgement
does not. Thus, believing and not withholding is the attitude justified by minimal
evidential support (p. 77).”

F&C go on to add the following two
clarifications with respect to (EC):

First, they note that saying that having
one’s evidence slightly support P
over ¬P is enough to justify
believing P is consistent with the
idea that beliefs are accompanied by different strengths of conviction.
Moreover, it is possible that beliefs themselves come in degrees, which
correspond with the strength of conviction implicated by them. Given this fact,
we may also hold that the strength of conviction with which an agent believes P (or their degree of belief in P) should mirror or be proportional to
how much their evidence supports P.
Hence, saying that having one’s evidence slightly support P over ¬P is sufficient
for belief does not imply that it is sufficient for having full confidence in P or believing P with full conviction.

Second, they emphasize that just because
one believes P, it does not follow
that one ought to act on one’s belief.If one believes P with a very
low level of conviction (or to a sufficiently minimal degree), it may be more
appropriate to wait for additional evidence (assuming the option is available)
rather than to act on one’s belief. These two points of clarification are meant
to bolster the plausibility and palatability of (EC).

F&C do not go into great detail
about what is entailed by an attitude being justified. They do note that “an
attitude’s being epistemically justified does not imply having any sort of duty
or obligation to take the attitude”(p. 79).However, it is plausible (and F&C would most certainly agree) that
an attitude is justified only if it is rationally permissible.It also seems plausible that an attitude that
is not justified is not rationally permissible. (Both of these claims are consistent with saying
that an attitude being justified does not entail any rational obligation to
adopt that attitude.)In sum, whether or
not an attitude is justified appears to covary with whether or not it is
rationally permissible, and not with whether or not it is rationally
obligatory.In order to make the notion
of justification a bit more concrete (and hence more amenable to appraisal), I
will frame my discussion of justification in terms of whether or not an
attitude is rationally permissible.

I wish to grant F&C’s contention
that having one’s evidence on balance slightly support P is enough for it to be rationally permissible to believe P, given the caveat about strength of
conviction or degrees of belief adumbrated above. However, I resist the
implication that it would be rationally impermissible to suspend P if one’s evidence very slightly
supported P over ¬P.This implication of (EC) seems particularly implausible in cases in
which one is aware that the evidence currently available is known to be limited
or incomplete.For example, suppose that
the evidence we currently have available slightly supports the proposition “String
Theory is true” over its negation. Suppose
further that we know that the evidence bearing on whether or not String Theory
is true is scarce or significantly incomplete. Under such circumstances, it
seems as though it would be rationally permissible (i.e., justified) in
suspending judgement about whether String Theory is true.If this is right, then one may be justified in
suspending P even if one’s available
evidence slightly supports P over ¬P.

To sum up, in cases in which we have
reason to think that our currently available evidence is incomplete, we may be
justified in suspending judgement even if on balance our evidence slightly
favours P.If this is right, then it follows that (EC)
is false.

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The Reasoner

Today my self-esteem hit an all time low when I stumbled across an argument proving conclusively that I don't exist. I’m quite distressed. This probably explains why my jeans are so loose-fitting. What’s equally upsetting is that I learned that non-existence does not exempt one from local or federal taxes.